<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>CSSForTextDispaly</title>
    <style>
        h2
        {
            display: none;
        }
    </style>

</head>
<body>
<h1>
    This is a head!
</h1>
<H2>
    This is a head can't see!
</H2>
<p>
    Hello World!
</p>
</body>
</html>